#pragma once
#include <memory>
#include <string>
using std::unique_ptr;
using std::string;

class dns
{
private:
	dns(void);
public:
	~dns(void);

public:
	static dns* instance(); // DONOT delete the pointer after use!
	string resolve(const string& host) const; 

private:
	static unique_ptr<dns> s_instance;
};

